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Dave Jones of EEVblog shows hand soldering of surface-mount parts, including drag soldering and tack-and-reflow of 0.5mm fine-pitch ICs, with solder paste and hot air.

NightHawkInLight shows how to make radiative sky cooling paint from grocery and hardware store materials, including a novel calcium carbonate microsphere synthesis. The paint can cool a surface below ambient air temperature in direct sunlight without electricity.

Matt Risinger covers installing a Zehnder ERV fresh-air system in a tight passive house, explaining balanced ventilation, the benefits of heat recovery and the costs involved.